update changelog

CHANGELOG.md

@@ -4,6 +4,8 @@ Please add a note of your changes below this heading if you make a Pull Request.
 ### Added
 * Communication watchdog feature.
 * `encoder.set_linear_count(count)` function.
+* Configurable encoder offset calibration distance and speed:`calib_scan_distance` and `calib_scan_omega`
+* Encoder offset calibration debug variable `calib_scan_response`
 
 # Releases
 ## [0.4.8] - 2019-02-25

tools/odrive/utils.py

@@ -198,7 +198,7 @@ def setup_udev_rules(logger):
     if os.getuid() != 0:
         logger.warn("you should run this as root, otherwise it will probably not work")
     with open('/etc/udev/rules.d/91-odrive.rules', 'w') as file:
-        file.write('SUBSYSTEM=="usb", ATTR{idVendor}=="1209", ATTR{idProduct}=="0d3[0-9]", MODE="0666"\n')
+        file.write('SUBSYSTEM=="usb", ATTR{idVendor}=="1209", ATTR{idProduct}=="0d3[0-9]", MODE="0666", ENV{ID_MM_DEVICE_IGNORE}="1"\n')
     subprocess.check_call(["udevadm", "control", "--reload-rules"])
     subprocess.check_call(["udevadm", "trigger"])
     logger.info('udev rules configured successfully')